As a viewer, I would be interested to know what is going to happen if I hear the voices with a black screen. I recently read the excerpts of Alexandra Casavant's The Voiceless Voice, and she started a few stories using dialogues. With the context she provides in the next sentences, it builds to a curiosity that keeps me going back for more. It is a well-done feat for a short story compilation about the power of our voices.
On the other hand, sometimes I find it easier to experiment later as I've established the plot line and characters, knowing that I've set the course right.